Received: 31 May 2018 Revised: 30 October 2018 Accepted: 26 November 2018 DOI: 10.1002/hipo.23060 RESEARCH ARTICLE Encoding of 3D head direction information in the human brain Misun Kim | Eleanor A. Maguire Wellcome Centre for Human Neuroimaging, Queen Square Institute of Neurology, Abstract University College London, London, United Head direction cells are critical for navigation because they convey information about which Kingdom direction an animal is facing within an environment. To date, most studies on head direction Correspondence encoding have been conducted on a horizontal two-dimensional (2D) plane, and little is known Eleanor Maguire, Wellcome Centre for Human Neuroimaging, Queen Square Institute of about how three-dimensional (3D) direction information is encoded in the brain despite humans Neurology, University College London, and other animals living in a 3D world. Here, we investigated head direction encoding in the 12 Queen Square, London WC1N 3AR, United human brain while participants moved within a virtual 3D “spaceship” environment. Movement Kingdom. was not constrained to planes and instead participants could move along all three axes in volu- Email:
[email protected] metric space as if in zero gravity. Using functional magnetic resonance imaging (fMRI) multivoxel Funding information Wellcome, Grant/Award Numbers: 101759/ pattern similarity analysis, we found evidence that the thalamus, particularly the anterior por- Z/13/Z, 102263/Z/13/Z, 203147/Z/16/Z; tion, and the subiculum encoded the horizontal component of 3D head direction (azimuth). In Samsung Scholarship contrast, the retrosplenial cortex was significantly more sensitive to the vertical direction (pitch) than to the azimuth.